1. Field of the Invention
This invention relates to electrical switches and, in particular, to a key-operated or push-button switch of reduced thickness or height. Still more particularly, the invention deals with an assemblage of such switches well adapted for use with the input keyboard of an electronic desk calculator.
2. Description of the Prior Art
The advent of large-scale integrated (LSI) circuits has led to the miniaturization of electronic desk calculators and numerous other electronic instruments. LSI circuits have even found their way into clocks, watches and like devices that have been built of purely mechanical means. With the application of LSI circuits to many such instruments, a need has arisen to reduce the size of hand-operated switches accompanying the LSI circuits.
Regarding electronic desk calculators, for example, the current trend is toward the minimization of their thickness. This objective is tantamount to the minimization of the thickness or height of the switches under the keyboards of the calculators. Prior art switches used in desk calculators (FIGS. 1 through 3 of the accompanying drawings) have been such, however, that their thickness has been approximately four millimeters at a minimum. The prior art switches are also objectionable in view of difficulties involved in their manufacture or assemblage and of their comparatively short service life.